1、Designation:D254902(Reapproved 2012)Standard Test Method forSeparation of Representative Aromatics and NonaromaticsFractions of High-Boiling Oils by Elution Chromatography1This standard is issued under the fixed designation D2549;the number immediately following the designation indicates the year of
2、original adoption or,in the case of revision,the year of last revision.A number in parentheses indicates the year of last reapproval.Asuperscript epsilon()indicates an editorial change since the last revision or reapproval.1.Scope1.1 This test method covers the separation and determina-tion of repre
3、sentative aromatics and nonaromatics fractionsfrom hydrocarbon mixtures that boil between 232 and 538C(450 and 1000F).Alternative procedures are provided for theseparation of 2 g or 10 g of hydrocarbon mixture.NOTE1Some components may not be eluted from the chromato-graphic column for some types of
4、samples under the conditions used inthis method.NOTE2Test Method D2007 is an alternative method of separatinghigh-boiling oils into polar compounds,aromatics,and saturates fractions.1.2 An alternative procedure is provided to handle samplesboiling below 232C(450F),but whose 5%point is above178C(350F
5、)as determined by Test Method D2887.Thisprocedure is given in Appendix X1.1.3 The values stated in acceptable SI units are to beregarded as the standard.The values given in parentheses areprovided for information purposes only.1.4 This standard does not purport to address all of thesafety concerns,i
6、f any,associated with its use.It is theresponsibility of the user of this standard to establish appro-priate safety and heal practices and determine the applicabilityof regulatory limitations prior to use.2.Referenced Documents2.1 ASTM Standards:2D2007 Test Method for Characteristic Groups in Rubber
7、Extender and Processing Oils and Other Petroleum-Derived Oils by the Clay-Gel Absorption Chromato-graphic MethodD2425 Test Method for Hydrocarbon Types in Middle Dis-tillates by Mass SpectrometryD2786 Test Method for Hydrocarbon Types Analysis ofGas-Oil Saturates Fractions by High Ionizing VoltageMa
8、ss SpectrometryD2887 Test Method for Boiling Range Distribution of Pe-troleum Fractions by Gas ChromatographyD3239 Test Method for Aromatic Types Analysis of Gas-OilAromatic Fractions by High Ionizing Voltage Mass Spec-trometry3.Terminology3.1 Definitions of Terms Specific to This Standard:3.1.1 aro
9、matics fractionthe portion of the sample des-orbed with the polar eluants.The aromatics fraction maycontain aromatics,condensed naphthenic-aromatics,aromaticolefins,and compounds containing sulfur,nitrogen,and oxy-gen atoms.3.1.2 nonaromatics fractionthe portion of the sampleeluted with n-pentane.Th
10、e nonaromatics fraction is a mixtureof paraffinic and naphthenic hydrocarbons if the sample is astraight-run material.If the sample is a cracked stock,thenonaromatics fraction will also contain aliphatic and cyclicolefins.4.Summary of Test Method4.1 A weighed amount of sample is charged to the top o
11、f aglass chromatographic column packed with activated bauxiteand silica gel.n-Pentane is added to the column to elute thenonaromatics.When all of the nonaromatics are eluted,thearomatics fraction is eluted by additions of diethyl ether,chloroform,and ethyl alcohol.4.2 The solvents are completely rem
12、oved by evaporation,and the residues are weighed and calculated as the aromaticsand nonaromatics fractions of the sample.5.Significance and Use5.1 The determination of compound types by mass spec-trometry requires,in some instances,a preliminary separationof the petroleum sample into representative
13、aromatics andnonaromatics fractions,as in Test Methods D2425,D2786,andD3239.This test method provides a suitable separation tech-nique for this application.1This test method is under the jurisdiction of ASTM Committee D02 onPetroleum Products,Liquid Fuels,and Lubricants and is the direct responsibil
14、ity ofSubcommittee D02.04.0C on Liquid Chromatography.Current edition approved April 15,2012.Published April 2012.Originallyapproved in 1966.Last previous edition approved in 2007 as D254902(2007).DOI:10.1520/D2549-02R12.2For referenced ASTM standards,visit the ASTM website,www.astm.org,orcontact AS
15、TM Customer Service at serviceastm.org.For Annual Book of ASTMStandards volume information,refer to the standards Document Summary page onthe ASTM website.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 6.Apparatus6.1 Chromatographic Colu
16、mns,as shown in Fig.1.Differ-ent chromatographic columns are provided for the analysis of2 and 10-g samples.6.2 Beakers,100,250,and 600-mL,inverted-rim type.36.3 Steam Bath.6.4 Electric Vibrator,for packing column.6.5 Weighing Bottles or Erlenmeyer Flasks,25 and 50 mL.7.Reagents and Materials7.1 Purity of ReagentsReagent grade chemicals shall beused in this test.Unless otherwise indicated,it is intended thatall reagents shall conform to the specifications of the Commit-tee on Analytical Reagents
